Hello to all Forumers of VIVAC..im a newbie here..from Subang Jaya..would like to share something with you about our DVVT System which are currently used in Viva, Kenari & MyVi.
What is DVVT?
DVVT stands for
Dynamic Variable Valve Timing. From the perspective of the Toyota Group, it would make sense to have this engine – which was jointly developed by
Toyota and
Daihatsu for small models – to be used as much as possible to have
good economies of scale. Perodua is also assembling the engine at its own plant so it is an obvious choice.
Layout of a 3 cylinder DVVT engine :
http://www.billzilla.org/vvtvtec.htm à U all kena tengok ni if tak paham ape yg I terang kat bawah..hehe.
How DVVT WorksDVVT and VVT-i (not VVTL-i) are identically the same system.(Tapi system tak sama dgn DOHC VTEC & DOHC Mivec..tetapi hampir sama dgn system DOHC 4AGE 20v Toyota).
The DVVT will activate by :
1. VVT Pulley
2. OCV Valve (Oil Control Valve @ Oil Solenoid)
3. Engine load/inlet manifold pressure (how you press your pedal - not like DOHC VTEC/DOHC MIVEC/DOHC 4AGE 20V which shift to high performance mode at certain specified RPM to operate cam timing@valve timing).
4. E.C.U
Perodua claims the DVVT system operates (DVVT bukak

) at around ~
3000rpm.
So bile u all slam your throttle pedal to the floor,and bila your rpm reach 3000rpm, your ECU (Electronic Control Unit @ Computer Box) akan hantar SIGNAL kepada OCV valve untuk 'bukak'..ketika ini oil pressure (tekanan minyak hitam) akan meningkat & akan flow through satu special gallery dalam #1 inlet cam bearing , melalui tengah inlet cam dan kepada DVVT@VVT pulley. Dalam pulley tu ada satu device (small piston) dan bila oil pressure cukup ia akan 'move outwards' dan karektor pulley DVVT@VVT pada INTAKE CAM pula memainkan peranan (EXHAUST CAM punya timing masih tetap).Timing pada intake camshaft yg dikontrol oleh pulley tadi telah diADVANCE secara automatic menyebabkan valve intake BUKAK LEBIH LAMA (longer intake duration) dan power dapat dirasai sehingga maximum rpm (bergantung kepada REDLINE engine kereta masing-masing)
Tak Faham Jugak??

Watch this ---->
http://www.youtube.com/watch?v=9A6S1NUjg_A&mode=related&search= And this --->
http://www.youtube.com/watch?v=dSZXepU7Sks&NR=1VIVA 660 (659cc)Engine Viva 660 (kod engine EF-VE) adalah RELIABLE & SELAMAT dan masih menjana kuasa untuk diperah sampai
7200~7500rpm (tinggi ni!!) dan torque maksimum berada sekitar 4500rpm.
Mengapa engine ni reliable & selamat ditarik tinggi?
1. Bore piston (68mm) adalah lebih besar daripada stroke crank (60.5mm) – oversquare engine. (Kancil 660 pun guna blok yang sama)
2. DVVT system (angin disedut lebih banyak & lama kedalam combustion cylinder
3. System DOHC (Double Overhead Cam) pada head engine yang mempunyai 2 camshaft (intake cam & exhaust cam) dan 12 valve. (Kancil 660 engine EF-CL hanya SOHC 6 valve – Carburator plak tu meanwhile Viva 660 using EFI – Electronic Fuel Injection)
Viva 660 (EF-VE) vs Kancil 660 (EF-CL) comparison.(standard vs standard)Redline Kancil 660 SOHC 6 valve carburator = 6400-6500rpm
Redline Viva 660 DOHC 12 valve dvvt Efi = 7200-
7500rpmTorque maximum Kancil 660 = 49Nm@6400rpm
Torque maximum Viva 660 =
58Nm@4400rpm
VIVA 850 (ED-VE) & VIVA 1.0 (EJ-VE) of course
MORE POWER than VIVA 660 in terms of horsepower and maximum torque because
displacement (cc) yang lebih.But these two engines tak boleh high-rev like EF-VE (Viva 660).Rev limit adalah 6000-6200rpm sahaja.
Why??

Because :
1. Viva 850 : Bore piston (66.6mm) adalah lebih KECIL daripada stroke crank (81mm) – undersquare engine. (Kancil 850 guna blok yg sama)
2. Viva 1.0 : Bore piston (72mm) adalah lebih KECIL daripada stroke crank (81mm) – undersquare engine. (Kelisa, MyVi & Kenari 1.0 guna blok yang sama)
(If u all tarik above 6200rpm pun no point because that’s where the power drops)
Viva 850 (ED-VE) vs Kancil 850 (ED-10) comparison. (Standard vs standard)Redline Kancil 850 SOHC 6 valve carburator = 5500rpm (max torque 63Nm@3800rpm)
Redline Viva 850 DOHC 12 valve dvvt Efi =
6200rpm (max torque
76Nm@4000rpm)
(Sorry untuk model Viva 1.0 I malas nak type coz the comparison is basically the same as above with Kelisa 1.0 but similar with Kenari 1.0 and MyVi 1.0 due to the same engine but some perodua exec told me Viva 1.0 is slightly better than the two coz they did a ‘port and polish’ job to all Vivas engine head – better airflow to combustion chambers)
And our DVVT ni jika tak silap i menggunakan ECU (Computer Box) oleh Daihatsu & di pasang di Philipine.Setiap ECU memainkan peranan penting. It's a close-loop as far as i know and it means not-programmable.(Means u need a
piggyback controller or
standalone ECU to fine-tune and enhance the true potential of your dvvt engine)
i.e ECU codes (for MyVi 1.0 Dohc DVVT) :
BZ040/BZ041/BZ042/BZ440As for now..i hope this helps..DVVT in our Viva also helps to
reduce fuel consumption (this also depends on how hard you slam your pedal @ throttle opening) and it's an environmentally friendly with low emmission for Green Peace.There is an 02 cencor connected to our exhaust manifold and emmission controlled via ECU.
So for now..Cheers and enjoy your Viva..take good care of her..